1. Field of the Invention
The invention relates in general to an electrical device, and more particularly to an optical disk drive and start-up operating method thereof.
2. Description of the Related Art
Along with the internet and multimedia industry progress, optical disks for storing audio and video data have replaced old cassettes. Optical disks have a greater data storage capacity than old cassettes, and can preserve the audio and video quality better and longer. Thus, optical disks, such as CD-ROM, DVD-ROM and CD-RW, have become the mainstream of the storage media market today.
Generally, after an idle period, an optical disk drive may enter a power saving mode to reduce the power consumption. At this time, a motor inside the optical disk drive stops, so that the generation of noise and heat can be reduced. Also, part of electronic components on the inside circuit board come to stop working. The power saving mode of the optical disk drive may include Standby mode and/or Sleep mode for example. When a user presses the play button, the optical disk drive will be woken up from the power saving mode and will play the data temporarily stored in a dynamic random access memory (DRAM). Before, the data temporarily stored in the DRAM is played out, the optical disk drive needs to complete a start-up operation, which includes accelerating the rotation speed of a spindle motor to reach the play rotation speed. Therefore, after the data temporarily stored in the DRAM is played out, the optical disc drive can play the data by reading the disc directly.
However, the optical disk drive may use the dynamic random access memory (DRAM) with less memory capacity and the spindle motor with slower acceleration due to manufacturing costs considerations. Accordingly, when the user presses the play button after the power saving mode, since the quantity of data temporarily stored in the DRAM may be insufficient, or the spindle motor with slower acceleration may require longer time to reach the play rotation speed, the optical disc drive may be failed to reach the play rotation speed to read the optical disk data before the data stored in the DRAM has been played out resulting in phenomenon of picture freeze or sound stuttering.
In addition, during the conventional start-up operation, the optical disk drive initializes the inside digital signal processor first. Then, the optical disk drive starts the laser diode driver of the optical pickup head. Next, the optical disk drive starts the motor driving circuit to accelerate the spindle motor, thereby reading the optical disk data. It takes a long time to complete the start-up operation and make the rotation speed of the spindle motor to reach the play rotation speed.